Radio telemetry reveals extensive dispersal capabilities of reintroduced Great Capricorn beetles (Cerambyx cerdo) in oak habitats at their Northern range limit
Data files
Mar 24, 2025 version files 10.10 KB
-
franzen__ICDIV-24-0278_beetle_data.zip
6.03 KB
-
README.md
4.07 KB
Abstract
Amid accelerating global biodiversity loss, reintroducing and translocating endangered species have become pivotal conservation strategies. This study used radio telemetry to investigate the dispersal and movement patterns of the reintroduced Great Capricorn Beetle (Cerambyx cerdo) within Tromtö Nature Reserve, Sweden.We tracked 50 beetles (29 females, 21 males) from 17 June 2022 to 17 July 2022, quantified their movements within the landscape, and recorded the distances moved across oak-rich areas at the northern edge of the species’ range.
Female beetles were significantly larger and heavier than males, with longer antennae. The beetles were relocated an average of 9.5 times. Total movement distances ranged from 2.8 m to 822.2 m, with no significant association of movement distance or movement speed with sex, body size or mating status.
We conclude that C. cerdo can reach oaks several hundred meters away and that dispersal distances were not associated with sex, body size or mating status. We recommend future studies employing more advanced telemetry techniques to refine our understanding of the species movement ecology and ensure successful reintroduction and survival.
Overview
This repository contains the dataset and R script used in the analysis of movement and morphological traits of Cerambyx cerdo for the associated publication. The dataset includes tracked movement data and morphological measurements for each individual beetle. The R script provides a reproducible pipeline for data cleaning, statistical analysis, and figure generation.
Files
beetle_data.csv
Description:
This dataset contains information on tracked movements and morphological characteristics of beetles. Each row corresponds to an individual beetle.
Variables:
- Tag_ID (Numeric): Unique identifier for each beetle.
- Sex (Character): Biological sex of the beetle:
M
: MaleF
: Female
- Body_size (Numeric): The length of the beetle’s body in millimetres (mm).
- Antenna (Numeric): The length of the beetle’s antenna in millimetres (mm).
- Thorax (Numeric): The width of the beetle’s thorax in millimetres (mm).
- Weight (Numeric): The body weight of the beetle in grams (g).
- total_distance (Numeric): The total distance moved by the beetle during the tracking period (metres).
- first_observation (Date): The beetle’s first recorded observation date (
DD/MM/YYYY
). - last_observation (Date): The beetle’s last recorded observation date (
DD/MM/YYYY
). - tracking_days (Numeric): The total number of days the beetle was tracked.
- movement_speed (Numeric): Average movement speed (metres per day).
- Mating (Character): Mating status of the beetle:
Mated
: Beetle was mated.Not Mated
: Beetle was unmated.
Franzen_c_cerdo_ICDIV-24-0278.r
Description:
This R script includes the full analysis pipeline for the study. It processes the beetle_data.csv
file, performs statistical analyses, and generates figures used in the publication.
Key Features:
- Data Import and Preparation:
- Reads the
beetle_data.csv
file. - Renames and formats columns for consistency.
- Handles missing values and performs data cleaning.
- Reads the
- Morphological Analysis:
- Calculates summary statistics (mean, SE) for traits like body size, antenna length, thorax width, and body weight.
- Conducts Welch’s t-tests to compare male and female traits.
- Movement Analysis:
- Computes movement metrics: total distance, tracking days, and movement speed.
- Tests for differences in movement patterns by sex and mating status using Welch’s t-tests.
- Fits linear models to assess relationships between movement and morphological traits.
- Visualization:
- Generates high-quality figures showing:
- Morphological differences by sex.
- Total distance and movement speed by sex.
- Relationships between body size and movement distance.
- Saves figures as high-resolution PNG files.
- Generates high-quality figures showing:
- Statistical Tests:
- Uses ANOVA, linear models, and correlation analyses for hypothesis testing.
- Outputs detailed statistical results for reproducibility.
Dependencies:
The script uses the following R packages:
dplyr
,ggplot2
,readxl
,car
,gridExtra
,broom
,tidyr
.
Execution Instructions:
- Place
beetle_data.csv
in the same directory as the R script. - Open the R script in RStudio or another R environment.
- Set the working directory to the file location.
- Run the script line by line or execute the entire script to reproduce the analyses.
Intended Use
These files allow users to:
- Reproduce the analyses presented in the manuscript.
- Extend or modify the analysis for additional research.
- Generate figures included in the publication.
Citation
If using this dataset or script, please cite the associated publication:
Contact
For further questions or issues regarding the data or script, please contact:
Markus Franzen\
markus.franzen@liu.se